Battery sheet testing system

Abstract

The application relates to the photovoltaic technical field and provides a cell piece testing system, which comprises a cooling plate used for bearing a cell piece to be tested and contacting the cell piece to be tested, and a bias light source arranged on a first side of the cooling plate and used for emitting bias light to the cell piece to be tested. The wavelength of the bias light generated by the bias light source is 500 nm-1000 nm. The bias light source emits the bias light to the cell piece to be tested. After the cell piece to be tested generates heat, the heat of the cell piece to be tested can be transferred to the cooling plate due to the contact between the cooling plate and the cell piece to be tested. Therefore, the cooling plate can cool the cell piece to be tested, so that the temperature of the cell piece to be tested can be reduced during the testing of the cell piece, and the testing accuracy is improved.

Description

Technical Field

[0001] This application relates to the technical field, and in particular to a battery cell testing system. Background Technology

[0002] During the production of solar cells, various tests need to be conducted on the cells, such as the External Quantum Efficiency (EQE) test.

[0003] During the testing process, bias light needs to be used to irradiate the solar cell to fill the base region of the cell with charge carriers, thereby reducing the recombination of photogenerated charge carriers. However, the electron-hole pairs generated by the bias light excitation release lattice vibration energy when recombinating, which will cause the temperature of the solar cell to rise, thus affecting the accuracy of the test. Utility Model Content

[0004] This application provides a solar cell testing system that can reduce the temperature of solar cells and improve the accuracy of testing during the testing process.

[0005] To achieve the above objectives, this application adopts the following technical solution: In a first aspect, a battery cell testing system is provided, comprising: a cooling plate for supporting and contacting the battery cell under test; and a bias light source disposed on a first side of the cooling plate for emitting bias light onto the battery cell under test, wherein the wavelength of the bias light emitted by the bias light source is 500nm-1000nm.

[0006] In conjunction with the first aspect, in some embodiments of the first aspect, the bias light source is an area array laser light source.

[0007] In conjunction with the first aspect, in some embodiments of the first aspect, the wavelength of the laser generated by the area array laser source is 800nm-1000nm.

[0008] In conjunction with the first aspect, in some embodiments of the first aspect, the cell testing system further includes: a monochromatic pulse light source, disposed on the first side, for emitting monochromatic pulse light to the cell under test.

[0009] In conjunction with the first aspect, in some embodiments of the first aspect, the monochromatic pulsed light source includes: a laser emitter located on the first side; a filter located between the first side and the laser emitter; and a chopper located between the first side and the filter.

[0010] In conjunction with the first aspect, in some embodiments of the first aspect, the cell testing system further includes an aperture located between the monochromatic pulse light source and the first side.

[0011] In conjunction with the first aspect, in some embodiments of the first aspect, the battery cell testing system further includes: an image acquisition device, disposed on the first side, for acquiring grayscale images of the battery cell to be tested.

[0012] In conjunction with the first aspect, in some embodiments of the first aspect, the number of monochromatic pulse light sources is multiple, and each monochromatic pulse light source emits a laser with a different wavelength. The device also includes a multi-channel lock-in amplifier connected to the image acquisition device.

[0013] In conjunction with the first aspect, in some embodiments of the first aspect, the angle between the line connecting each monochromatic pulse light source to a point on the surface of the cooling plate and the surface of the cooling plate is the same.

[0014] In conjunction with the first aspect, in some embodiments of the first aspect, the number of monochromatic pulse light sources is one, and the monochromatic pulse light source further includes: a single-channel lock-in amplifier connected to the image acquisition device.

[0015] In conjunction with the first aspect, in some embodiments of the first aspect, the cooling plate includes a first support portion and a second support portion, the first support portion being used to support the battery cell to be tested, and the second support portion being used to support a standard battery cell.

[0016] In conjunction with the first aspect, in some embodiments of the first aspect, the cooling plate includes: a plate body having a cavity; and coolant located within the cavity.

[0017] Based on the battery cell testing system provided by this utility model, a bias light source emits bias light towards the battery cell under test. After the battery cell under test heats up, the heat of the battery cell under test can be transferred to the cooling plate because the cooling plate is in contact with the battery cell under test. Therefore, the cooling plate can cool the battery cell under test, thereby reducing the temperature of the battery cell and improving the accuracy of the test during the testing process. Attached Figure Description

[0018] Figure 1 A battery cell testing system provided in this application; Figure 2 This application provides yet another battery cell testing system.

[0019] Figure label: The components include: a battery cell testing system-10, a battery cell under test-20, a cooling plate-101, a first support unit-1011, a second support unit-1012, a bias light source-102, a monochromatic pulse light source-103, a laser emitter-1031, a filter-1032, a chopper-1033, an aperture-104, an image acquisition device-105, a single-channel lock-in amplifier-106, a multi-channel lock-in amplifier-107, and a standard battery cell-30. Detailed Implementation

[0020] In this embodiment of the invention, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" or "for example" in this embodiment of the invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner to facilitate understanding.

[0021] Furthermore, to facilitate a clear description of the technical solutions of the embodiments of this utility model, the terms "first" and "second" are used in the embodiments of this utility model to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0022] It is understood that the term "embodiment" used throughout the specification means that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of the present invention. Therefore, the various embodiments throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It is understood that in the various embodiments of the present invention, the sequence number of each process does not imply the order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0023] It is understood that in this utility model, "when," "if," and "if" all refer to the corresponding processing that will be carried out under certain objective circumstances, and are not limited to a specific time, nor do they require a judgment action to be performed, nor do they imply any other limitations.

[0024] It is understood that some optional features in the embodiments of this utility model can be implemented independently in certain scenarios without relying on other features, such as the current solution on which they are based, to solve the corresponding technical problems and achieve the corresponding effects. Alternatively, they can be combined with other features as needed in certain scenarios. Correspondingly, the device given in the embodiments of this utility model can also implement these features or functions, which will not be elaborated here.

[0025] In this utility model, unless otherwise specified, the same or similar parts between the various embodiments can be referred to each other. In the various embodiments and implementation methods of this utility model, unless otherwise specified or logically conflicting, the terminology and / or descriptions between different embodiments and between the implementation methods of different embodiments are consistent and can be mutually referenced. The technical features in different embodiments and between the implementation methods of different embodiments can be combined according to their inherent logical relationships to form new embodiments, implementation methods, implementation methods, or implementation approaches. The following embodiments of this utility model do not constitute a limitation on the scope of protection of this utility model.

[0026] During the production of solar cells, various tests need to be conducted on the cells, such as the External Quantum Efficiency (EQE) test.

[0027] During the testing process, bias light needs to be used to irradiate the solar cell to fill the base region of the cell with charge carriers, thereby reducing the recombination of photogenerated charge carriers. However, the electron-hole pairs generated by the bias light excitation release lattice vibration energy when recombinating, which will cause the temperature of the solar cell to rise, thus affecting the accuracy of the test.

[0028] To address the aforementioned problems, this utility model provides a battery cell testing system, such as... Figure 1 or Figure 2 As shown, the battery cell testing system 10 includes: a cooling plate 101 for supporting the battery cell 20 under test and contacting the battery cell 20 under test; and a bias light source 102 disposed on the first side of the cooling plate 101 for emitting bias light to the battery cell 20 under test, wherein the wavelength of the bias light generated by the bias light source is 500nm-1000nm.

[0029] For example, the wavelength of the bias light generated by the bias light source 102 is 500nm, 600nm, 700nm, 800nm, 900nm, or 1000nm. Of course, the wavelength of the bias light generated by the bias light source 102 can also be other values, and this invention does not impose specific limitations on this. Thus, setting the wavelength of the bias light generated by the bias light source 102 within a suitable range can avoid insufficient excitation depth of the tested battery cell 20 due to an excessively short wavelength, which would affect the accuracy of the test. It can also avoid the bias light directly penetrating the tested battery cell 20 due to an excessively long wavelength, preventing effective excitation and thus affecting the accuracy of the test. Setting a suitable wavelength for the bias light generated by the bias light source 102 can improve the accuracy of the test of the tested battery cell 20.

[0030] Based on the battery cell testing system provided by this utility model, the bias light source 102 emits bias light to the battery cell 20 under test. After the battery cell 20 under test heats up, the heat of the battery cell 20 under test can be transferred to the cooling plate 103 because the cooling plate 103 is in contact with the battery cell 20 under test. Therefore, the cooling plate 103 can cool the battery cell 20 under test, thereby reducing the temperature of the battery cell and improving the accuracy of the test during the battery cell testing process.

[0031] The cell testing system 10 includes a cooling plate 101, which comprises: a plate body having a cavity; and a coolant located within the cavity. Thus, since the coolant is disposed within the cavity of the cooling plate 101, the heat from the cooling plate 101 can be transferred to the coolant, improving the cooling effect of the cooling plate 101.

[0032] In some embodiments, the cavity of the cooling plate 101 can be closed, that is, the coolant inside the cavity of the cooling plate 101 is not in communication with the outside, thereby improving the overall integrity of the cooling plate 101.

[0033] In some other embodiments, the cavity of the cooling plate 101 may also be open, that is, the coolant inside the cavity of the cooling plate 101 is in communication with the outside. In this way, the coolant with a higher temperature inside the cavity of the cooling plate 101 can be transferred to the outside of the cooling plate 101, and the heat of the coolant can be dissipated outside the cooling plate 101, thereby further improving the cooling efficiency of the cooling plate 101.

[0034] The cooling plate 101 can be made of copper, aluminum or iron. Of course, the cooling plate 101 can also be made of other materials. This utility model does not impose any specific restrictions on this.

[0035] In addition to the surface that contacts the battery cell 20 under test, at least one other surface of the cooling plate 101 may be provided with heat dissipation fins. For example, heat dissipation fins may be provided on the surface of the cooling plate 101 facing the second side, with the second side opposite to the first side; or heat dissipation fins may be provided on all four sides of the cooling plate 101; or heat dissipation fins may be provided on both the surface of the cooling plate 101 facing the second side and on all four sides of the cooling plate 101. Thus, because the contact area between the heat dissipation fins and the air is large, the heat from the cooling plate 101 can be dispersed into the air through the heat dissipation fins, improving the heat dissipation efficiency of the cooling plate 101.

[0036] The coolant can be deionized water or ethylene glycol. Of course, the coolant can also be other materials, and this utility model does not impose any specific restrictions on it.

[0037] The specific heat capacity of the coolant can be between 3.3 kJ / (kg·K) and 3.9 kJ / (kg·K). For example, the specific heat capacity of the coolant can be 3.3 kJ / (kg·K), 3.4 kJ / (kg·K), 3.5 kJ / (kg·K), 3.6 kJ / (kg·K), 3.7 kJ / (kg·K), 3.8 kJ / (kg·K), or 3.9 kJ / (kg·K). Of course, the specific heat capacity of the coolant can also have other values, and this invention does not impose specific limitations on this. In this way, by setting the specific heat capacity of the coolant within a suitable range, it is possible to avoid the specific heat capacity of the coolant being too low, resulting in a low heat absorption efficiency of the cooling plate 101 and a reduced efficiency in absorbing the heat transferred by the battery cell 20 under test. It is also possible to avoid the specific heat capacity of the coolant being too high, resulting in a low heat dissipation efficiency of the coolant and a longer cooling time, thereby reducing the testing frequency of the battery cell testing system 10. Setting a suitable specific heat capacity for the coolant can increase the efficiency of the coolant in absorbing the heat transferred by the battery cell 20 under test, thereby increasing the testing frequency of the battery cell testing system 10.

[0038] The cooling plate 101 includes a first support portion 1011 and a second support portion 1012. The first support portion 1011 supports the solar cell 20 under test, and the second support portion 1012 supports a standard solar cell 30. The standard solar cell 30 is a solar cell with precisely known performance parameters that has undergone rigorous calibration and standardization. Thus, since the second support portion 1212 of the cooling plate 101 supports the standard solar cell 30, when testing the solar cell 20 under test, the standard solar cell 30 can be used to calibrate the test results of the solar cell 20 under test, and can also be used to detect the light intensity emitted by a bias light source or a monochromatic pulsed light source, ensuring that each test is conducted under completely consistent and standard lighting conditions, thereby improving the accuracy of the test of the solar cell 20 under test.

[0039] The test cell 20 and the standard cell 30 can be TOPCon cells, BC cells, or HJT cells. Of course, the test cell 20 and the standard cell 30 can also be other types of cells. This utility model does not impose any specific restrictions on them.

[0040] The cell testing system 10 includes a bias light source 102, which emits bias light to the cell under test 20. The bias light emitted by the bias light source 102 can put the cell under test 20 into a working state so that the actual performance parameters of the cell under test 20 under illumination conditions can be measured in the future, thereby improving the accuracy of the test of the cell under test 20.

[0041] The optical power density of the bias light source 102 can be between 0.4 Sun and 0.6 Sun. For example, the optical power density of the bias light source 102 can be 0.4 Sun, 0.5 Sun, or 0.6 Sun. Of course, the optical power density of the bias light source 102 can also be other values, and this utility model does not impose specific limitations on this. Thus, setting the optical power density of the bias light source 102 within a suitable range can avoid the accuracy of the test of the battery cell 20 being reduced due to the optical power density being too low, which would fail to eliminate the capacitance effect. Conversely, it can also avoid the accuracy of the test of the battery cell 20 being reduced due to the optical power density being too high, which would cause the temperature of the battery cell 20 to become too high after irradiation. Setting a suitable optical power density for the bias light source 102 can improve the accuracy of the test of the battery cell 20.

[0042] The bias light source 102 can be a planar laser light source, an LED array light source, a halogen tungsten light source, or a bromide tungsten light source. Of course, the bias light source 102 can also be other types of light sources, and this utility model does not impose specific limitations on this. Preferably, the bias light source 102 is a planar laser light source. In this way, since the control response speed of the planar laser light source is faster, the testing efficiency of the battery cell 20 under test can be improved. At the same time, the laser generated by the planar laser light source can directly excite the battery cell 20 under test to generate electron-hole pairs, reduce the heat energy generated by the battery cell 20 under test during the exciton relaxation process, reduce the heat generated by the battery cell 20 under test due to bias light irradiation, and further improve the accuracy of the test of the battery cell 20 under test.

[0043] The wavelength of the laser generated by the area array laser source can be between 800nm ​​and 1000nm. For example, the wavelengths of the laser generated by the area array laser source are 800nm, 850nm, 900nm, 950nm, and 1000nm. Of course, the wavelength of the laser generated by the area array laser source can also be other values, and this utility model does not impose specific limitations on this. Thus, setting the wavelength of the laser generated by the area array laser source within a suitable range can avoid insufficient excitation depth of the tested solar cell 20 due to an excessively short wavelength, which would affect the accuracy of the test of the solar cell 20. It can also avoid the laser directly penetrating the tested solar cell 20 due to an excessively long wavelength, which would prevent the tested solar cell 20 from being effectively excited, thus affecting the accuracy of the test. Setting a suitable wavelength for the laser generated by the area array laser source can improve the accuracy of the test of the solar cell 20.

[0044] For example, when the cell under test 20 is a BC cell, the wavelength of the laser generated by the area array laser source is 808nm. Thus, for the BC cell, the optimal excitation wavelength of the bias light is 808nm, and the incident depth of the bias light can reach 80um, which is well matched with the thickness of the BC cell and improves the irradiation effect of the bias light.

[0045] like Figure 1 or Figure 2 As shown, the cell testing system 10 may further include a monochromatic pulse light source 103, disposed on the first side of the cooling plate 101, for emitting monochromatic pulse light onto the cell under test 20. The monochromatic pulse light source 103, also known as a test light source, can emit monochromatic pulse light onto the cell under test 20 to test its performance. Because the monochromatic pulse light source 103 emits monochromatic pulse light, the irradiation time of the monochromatic pulse light onto the cell under test 20 is extremely short, which can reduce the heat generated by the cell under test 20 and improve the accuracy of the test.

[0046] The number of monochromatic pulse light sources 103 can be one or more, and this invention does not impose a specific limitation on this. When there are multiple monochromatic pulse light sources 103, each monochromatic pulse light source 103 emits a laser with a different wavelength. In this way, the test cell 20 can be tested simultaneously under multiple wavelength laser irradiation, thereby improving the testing efficiency of the test cell 20.

[0047] When there are multiple monochromatic pulse light sources 103, the angle formed by the line connecting each monochromatic pulse light source 103 to a point on the surface of the cooling plate 101 and the surface of the cooling plate 101 is the same. In this way, the laser emitted by each monochromatic pulse light source 103 has the same incident angle on the surface of the battery cell 20 under test. This can avoid the test error caused by different incident angles of the laser emitted by the pulse light source on the surface of the battery cell 20 under test, thereby improving the accuracy of the test of the battery cell 20 under test.

[0048] like Figure 1 or Figure 2As shown, the monochromatic pulse light source 103 includes: a laser emitter 1031 located on the first side of the cooling plate 101; a filter 1032 located between the first side of the cooling plate 101 and the laser emitter 1031; and a chopper 1033 located between the first side of the cooling plate 101 and the filter 1032. Thus, after the laser emitter 1031 emits laser light, the filter 1032 can filter out the frequency-doubled light and stray light in the laser, improving the purity of the laser light illuminating the battery cell 20 under test. The chopper 1033 can convert the laser light from continuous light into monochromatic pulse light, allowing the laser light from the laser emitter 1031 to illuminate the battery cell 20 under test in the form of monochromatic pulse light. Therefore, by having the laser emitter 1031, filter 1032, and chopper 1033 work together, highly pure monochromatic pulse light can be emitted onto the battery cell 20 under test.

[0049] The laser emitter 1031 is an electro-optical device capable of generating laser light, which can emit laser light with good directionality, monochromaticity, coherence, and brightness. For example, the laser emitted by the laser emitter 1031 is white, thus simulating the working state of the battery cell 20 under test in a real environment and improving the accuracy of the test of the battery cell 20.

[0050] The laser emitter 1031 can be a free-electron laser, a liquid laser, a semiconductor laser, or a gas laser. Of course, the laser emitter 1031 can also be other types of laser emitters, and this utility model does not impose any specific limitations on this.

[0051] Filter 1032 is a device that can select a specific wavelength of laser light from multiple different wavelengths and suppress or eliminate other wavelengths of laser light.

[0052] Filter 1032 can be a long-pass filter, which allows lasers with wavelengths longer than a certain value to pass through with high transmission while blocking lasers with wavelengths shorter than that value.

[0053] The chopper 1033 can convert the laser emitted by the laser emitter 1031 from continuous light into monochromatic pulsed light. By adjusting the operating frequency of the chopper 1033, the pulse frequency of the monochromatic pulsed light illuminating the battery cell 20 under test can be adjusted.

[0054] The chopper 1033 can be a rotary blade chopper, a vibrating blade chopper, an electro-optical chopper, or an acousto-optical chopper. Of course, the chopper 1033 can also be other types of choppers, and this utility model does not impose any specific limitations on this.

[0055] like Figure 1 or Figure 2As shown, the solar cell testing system 10 may further include an aperture 104 located between the monochromatic pulse light source and the first side of the cooling plate 101. The aperture 104 is provided with a light-transmitting hole. By adjusting the shape and size of the light-transmitting hole of the aperture 104, the shape, size, and uniformity of the laser beam irradiating the solar cell 20 under test can be precisely controlled, thereby improving the controllability and accuracy of the testing of the solar cell 20 under test.

[0056] The aperture 104 can be a fixed aperture, a variable aperture, or a knife-edge aperture. Of course, the aperture 104 can also be other types of apertures, and this utility model does not impose any specific limitations on this.

[0057] like Figure 1 or Figure 2 As shown, the battery cell testing system 10 may further include an image acquisition device 105, disposed on the first side of the cooling plate 101, for acquiring grayscale images of the battery cell 20 under test. Thus, after acquiring the grayscale image of the battery cell 20 under test, the image acquisition device 105 can send it to a processor so that the processor can analyze the grayscale image and obtain the test results of the battery cell 20 under test.

[0058] The image acquisition device 105 can also be called a photoluminescence imager or a PL imager.

[0059] The image acquisition device 105 can be a scanning PL imager, an area array camera PL imager, an infrared thermal imager PL imager, or a microscope integrated PL imager. Of course, the image acquisition device 105 can also be other types of equipment, and this utility model does not impose specific limitations on it.

[0060] A grayscale image of the battery cell 20 under test is an image that contains only the brightness information of the battery cell 20 under test, but not the color information of the battery cell 20 under test. It can be used to analyze the performance or defects of the battery cell 20 under test.

[0061] In some embodiments, when the number of monochromatic pulse light sources is one, such as Figure 1 As shown, the cell testing system 10 may further include a single-channel lock-in amplifier 106 connected to the image acquisition device 105. Thus, the single-channel lock-in amplifier 106 can remove noise from the signal acquired by the image acquisition device 105, improving the signal-to-noise ratio and thereby enhancing the accuracy of the test of the cell under test 20.

[0062] The single-channel lock-in amplifier 106 can be an analog lock-in amplifier or a digital lock-in amplifier, and this utility model does not impose any specific limitations on it.

[0063] In some other embodiments, when there are multiple monochromatic pulse light sources, such as... Figure 2As shown, the cell testing system 10 may further include a multi-channel lock-in amplifier 107 connected to the image acquisition device 105. Thus, when the cell under test 20 is irradiated by multiple lasers of different wavelengths, the multi-channel lock-in amplifier 107 can separate the signal corresponding to each wavelength of laser and remove noise from each signal, improving the signal-to-noise ratio of the signal acquired by the image acquisition device 105, thereby improving the accuracy and efficiency of the testing of the cell under test 20.

[0064] The multi-channel lock-in amplifier 107 can be an analog lock-in amplifier or a digital lock-in amplifier, and this utility model does not impose any specific limitations on it.

[0065] The cell testing system 10 may also include a light-transmitting plate and a fixture. In practical applications, the cell to be tested 20 can be placed between the light-transmitting plate and the cooling plate 101, and then the fixture can be used to fix the cell to be tested 20, the light-transmitting plate and the cooling plate 101. The laser shines on the surface of the cell to be tested 20 through the light-transmitting plate. In this way, foreign objects or fixtures can be prevented from damaging the cell to be tested 20, thus improving the safety of the cell to be tested 20.

[0066] Based on the battery cell testing system 10 provided by this utility model, the battery cell 20 to be tested can be tested through the following multiple steps: First, the battery cell 20 to be tested undergoes pretreatment such as cleaning.

[0067] This ensures that the surface of the battery cell 20 under test is clean, preventing dust and other impurities on the surface of the battery cell 20 from affecting the test results.

[0068] Next, the battery cell 20 to be tested is placed on the first support portion 1011 of the cooling plate 101, and the standard battery cell 30 is placed on the second support portion 1012 of the cooling plate 101.

[0069] This ensures that the environment in which the cell under test 20 and the standard cell 30 are located is consistent, thus improving the effectiveness of the calibration test results.

[0070] Next, turn on the bias light source 102 so that the bias light emitted by the bias light source 102 shines on the battery cell 20 under test, so that the battery cell 20 under test is in working state.

[0071] Next, the laser emitter 1031, filter 1032, and chopper 1033 are turned on, and the light-transmitting aperture of the aperture 104 is adjusted to a specific state, so that the laser emitter 1032 emits laser light. The laser light emitted by the laser emitter 1032 has a specific wavelength and a specific frequency after passing through the filter 1032 and the chopper 1033. After passing through the aperture 104, it finally illuminates the surface of the battery cell 20 under test, causing the battery cell 20 under test to produce photoluminescence.

[0072] Secondly, during the process of the laser emitter 1031 emitting laser light onto the surface of the battery cell 20 under test, the image acquisition device 105 and the lock-in amplifier work together to acquire the photoluminescence signal of the battery cell 20 under test and convert it into a grayscale image.

[0073] Finally, the grayscale image is transmitted to the processor in the cell testing system 10. The processor has a built-in program that can analyze the performance or defects of the cell under test 20 based on the grayscale image and obtain the analysis results.

[0074] Although the present invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.

[0075] Although the present invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of the present invention. Accordingly, this specification and drawings are merely exemplary descriptions of the present invention as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and modifications of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and modifications.

Claims

1. A battery cell testing system, characterized in that, The battery cell testing system includes: A cooling plate is used to support the battery cell under test and to contact the battery cell under test. A bias light source is disposed on the first side of the cooling plate and is used to emit bias light to the battery cell under test. The wavelength of the bias light generated by the bias light source is 500nm-1000nm.

2. The battery cell testing system according to claim 1, characterized in that, The bias light source is a planar laser light source.

3. The battery cell testing system according to claim 2, characterized in that, The wavelength of the laser generated by the area array laser source is 800nm-1000nm.

4. The battery cell testing system according to claim 1, characterized in that, The battery cell testing system also includes: A monochromatic pulse light source is located on the first side and is used to emit monochromatic pulse light to the battery cell under test.

5. The battery cell testing system according to claim 4, characterized in that, The monochromatic pulse light source includes: The laser emitter is located on the first side; A filter is located between the first side and the laser emitter; A chopper is located between the first side and the filter.

6. The cell testing system according to claim 4, characterized in that, The battery cell testing system also includes: An aperture is located between the monochromatic pulse light source and the first side.

7. The cell testing system according to claim 4, characterized in that, The battery cell testing system also includes: An image acquisition device is located on the first side and is used to acquire grayscale images of the battery cell under test.

8. The cell testing system according to claim 7, characterized in that, The device includes multiple monochromatic pulse light sources, each emitting laser light with a different wavelength. A multi-channel lock-in amplifier is connected to the image acquisition device.

9. The cell testing system according to claim 8, characterized in that, The angle between the line connecting each monochromatic pulse light source to a point on the surface of the cooling plate and the surface of the cooling plate is the same.

10. The cell testing system according to claim 7, characterized in that, The number of the monochromatic pulse light source is one, and the monochromatic pulse light source further includes: A single-channel lock-in amplifier is connected to the image acquisition device.

11. The battery cell testing system according to claim 1, characterized in that, The cooling plate includes a first support portion and a second support portion. The first support portion is used to support the battery cell under test, and the second support portion is used to support a standard battery cell.

12. The cell testing system according to any one of claims 1-11, characterized in that, The cooling plate includes: The plate-shaped body has a cavity; Coolant is located inside the cavity.

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